It has been recognized that speech or audio being projected or transmitted into a region by an audio announcement system is not necessarily intelligible merely because it is audible. In many instances, such as sports stadiums, airports, buildings and the like, speech delivered into a region may be loud enough to be heard but it may be unintelligible. Such considerations apply to audio announcement systems in general as well as those which are associated with fire safety, building or regional monitoring systems.
The need to output speech messages into regions being monitored in accordance with performance-based intelligibility measurements has been set forth in one standard, namely, NFPA 72-2002. It has been recognized that while regions of interest, such as conference rooms or office areas may provide very acceptable acoustics, some spaces such as those noted above, exhibit acoustical characteristics which degrade the intelligibility of speech.
It has also been recognized that regions being monitored may include spaces in one or more floors of a building, or buildings exhibiting dynamic acoustic characteristics. Building spaces are subject to change over time as occupancy levels vary, surface treatments and finishes are changed, offices are rearranged, conference rooms are provided, auditoriums are incorporated and the like.
One approach for monitoring speech intelligibility due to such changing acoustic characteristics in monitored regions has been disclosed and claimed in U.S. patent application Ser. No. 10/740,200 filed Dec. 18, 2003, entitled “Intelligibility Measurement of Audio Announcement Systems” and assigned to the assignee hereof. The '200 application is incorporated herein by reference.
One approach for improving the intelligibility of speech messages in response to changes in such acoustic characteristics in monitored region has been disclosed and claimed in U.S. patent application Ser. No. 11/319,917 filed Dec. 28, 2005, entitled “System and Method of Detecting Speech Intelligibility and of Improving Intelligibility of Audio Announcement Systems in Noisy and Reverberant Spaces” and assigned to the assignee hereof. The '917 application is incorporated herein by reference.
There is a continuing need to measure speech intelligibility in accordance with NFPA 72-2002 after remediation of the speech messages has been undertaken in one or more monitored regions.
Thus, there continues to be an ongoing need for improved, more efficient methods and systems of measuring speech intelligibility in regions of interest following the remediation of speech messages so as to improve such intelligibility. It would also be desirable to be able to incorporate some or all of such remediation capability in a way that takes advantage of ambient condition detectors in a monitoring system which are intended to be distributed throughout a region being monitored. Preferably, the measurement of speech intelligibility of speech messages with remediation could be incorporated into the detectors being currently installed, and also be cost effectively incorporated as upgrades to detectors in existing systems as well as other types of modules.